The master patient index must, at a minimum, include sufficient information to

• A. uniquely identify the patient
• B. link to the patient's insurance coverage
• C. store the patient's entire health record
• D. record the patient's favorite color

Answer: (A)

The central idea here is that the master patient index is all about making sure you can uniquely identify a person across the health system. Because people can share names or have similar demographics, the MPI needs enough identifying details to tell one patient apart from another. A reliable, unique identifier for the patient (often a master patient number) paired with essential demographic data—like full name, date of birth, and gender—lets the system match the right records to the right person and avoid mix-ups or duplicates across clinics, departments, and databases. This function is the core purpose of the MPI; it isn’t meant to store the entire health record, nor to hold insurance details, nor to track irrelevant facts like a favorite color. By ensuring a unique identity is attached to every patient, the MPI provides a stable reference point for linking and retrieving the correct health information when needed.